I can't figure out why. I just get this error. And it's true that there is no such part, but this has always worked before. I should be able to pull on my export as an ExportFactory`1 without making any changes as long as the PartCreationPolicy
is anything but Shared, which it is. I'm using the MEF 2 Preview getting the 404 equivalent of MEF.

No exports were found that match the constraint '((exportDefinition.ContractName = "System.ComponentModel.Composition.ExportFactory(MyEntity)") && (exportDefinition.Metadata.ContainsKey("ExportTypeIdentity") && "System.ComponentModel.Composition.ExportFactory(MyEntity)".Equals(exportDefinition.Metadata.get_Item("ExportTypeIdentity"))))'.

I was then reminded that MEF does not support open generic types. Which this is. And while on that topic. Can we expect open generic type support in the near future? I know that Glenn
blogged about this but then I have to grab that from MEF Contrib and I want to avoid that. Is there maybe some other way I can leverage this in a generic fashion? So that in the end, I can do:

container.GetExport<Factory<T>>();

...and it will work! I should already be able to do this but it will have to create a strongly typed object for each type which seems a bit verbose.

I haven't tested this exactly, but it should work. The reason why this is needed is because ExportFactory relies on a specific ImportDefinition that we create under the hood for imports on parts. This works because in this case
we dynamically create an import of ExportFactory. Glenn